Question

There are 84 students in a speech contest. Yesterday, 1/4 of them gave their speeches. Today, 3/7 of the remaining students gave their speeches. How many students still haven't given their speeches?

Answer 1

Answer: 27 students
First turn 1/4 and 3/7 into common denominators and add; 7/28+12/28=19/28
Subtract: 28/28-19/28=9/28
To find how many remain multiply: 9/28*84= 27

Answer 2

36

Explanation:

Total students un the contest = 84

Number of students who gave their speech yesterday:-

`(1)/(4) \: of \: total \\ = (1)/(4) * 84 \\ = 21`

so 21 students gave their speech yesterday

• remaining students = 84 - 21

= 63

Number of students who gave their speech today:-

`(3)/(7) \: of \: remaining \\ = (3)/(7) * 63 \\ = 27`

Number of students who have given their speech:-

= 21 + 27

= 48

Number of students who still haven't given their speech :-

= total - 48

= 84 - 48

= 36